Managed aquifer recharge is the intentional recharge of an aquifer under controlled conditions, either by injection or infiltration, in order to store a water source for later abstraction and use (indirect reuse), or for environmental benefits.
Potential sources of recharge water include, but are not limited to, treated wastewater, urban stormwater or groundwater drawn from other aquifers. Some level of pre-treatment of the source water will generally be required prior to recharging the aquifer, depending on the outcome of environmental and health risk assessments.
Generally, infiltration of rainwater via infiltration systems (such as soak wells, infiltration trenches, detention or infiltration basins, or vegetated areas) as a consequence of urbanisation is not considered as managed aquifer recharge. There may be opportunities for collection or redirection of urban stormwater for managed aquifer recharge, subject to satisfying the ecological water requirements of ecosystems that previously received stormwater input.
Managed aquifer recharge may not be feasible on all sites, due to hydrogeological, environmental or cost limitations. Where appropriate, managed aquifer recharge proposals should be considered early in the land planning process through the Better urban water management framework (WAPC 2008).
The Department of Water encourages managed aquifer recharge activities that maximise the use of our limited groundwater resources, provided that the recharge and recovery operations do not have an adverse impact on the groundwater system, the environment, or existing groundwater users through changes in water quality or quantity.
The Department of Water has developed a state-wide policy on Managed aquifer recharge in Western Australia to address environmental and allocation management impacts of managed aquifer recharge. This policy aligns with the environmental risk assessment approach taken in the Australian Guidelines for Water Recycling: Managing Health and Environmental Risks (Phase 2) Managed Aquifer Recharge (July 2009).
For more information on managed aquifer recharge and a copy of the Department of Water policy click here.
Further reading on managed aquifer recharge is provided with the Australian Government's Waterlines Report Series No. 13 (February 2009) – Managed aquifer recharge: An Introduction, undertaken by CSIRO on behalf of the National Water Commission.